1. Field of the Invention
The present invention relates to a connecting element for fuel injection systems for connecting a fuel injection valve to a fuel-conducting component, and to a fuel injection system having such a connecting element. Specifically, the present invention relates to the area of fuel injection systems for mixture-compressing externally ignited internal combustion engines.
2. Description of the Related Art
From published German patent application document DE 10 2005 020 380 A1, a fuel injection device is known that is distinguished by a design that decouples sound. The known fuel injection device includes a fuel injection valve, a receptacle bore for the fuel injection valve in a cylinder head, and a fuel distributor line having a connecting piece into which the fuel injection valve is brought in partly overlapping fashion. In a possible embodiment, a connecting element is provided that on the one hand grasps a holding collar of the fuel injection valve in the region of a housing shoulder, and on the other hand is connected to the connecting piece by a non-material connection, for example a snap connection. The connecting body is realized with a tubular shape, and has an opening for clamping an electrical connecting plug of the fuel injection valve. Outside this opening, the connecting body can be realized in 360° circumferential fashion. On the housing shoulder, the fuel injection valve is grasped by a holding collar of the connecting body, so that the fuel injection valve is freely suspended with a spacing relative to a radially running shoulder of the receptacle bore. On its end facing the connecting piece, the connecting body has, seen circumferentially, two oppositely situated slits that for example have an opening of approximately 90°. The slits are grasped by a clip-shaped, U-shaped snap ring. In addition, the snap ring engages, in the circumferential region of the slits in the connecting body, in two slit-shaped grooves on the circumference of the connecting piece for the secure fastening of the connecting body on the fuel distributor line. A hold-down clamp is also provided.
The embodiment of the fuel injection device known from published German patent application document DE 10 2005 020 380 A1 has the disadvantage that vibrations are transmitted from the fuel injection valve to the connecting piece via the connecting body and the snap ring. In addition, the embodiment requires a large constructive outlay, and is comparatively unstable due to a long lever arm of the connecting body. This also has a disadvantageous effect on the ease of installation.
Specifically in the case of electromagnetic high-pressure injection valves, which can be used in gasoline engines having direct injection, a noticeable and disturbing contribution may be made to the overall noise level of the engine, which can be described as valve ticking. Such valve ticking arises due to the rapid opening and closing of the fuel injection valve, in which the valve needle is moved to its respective end stop positions with a high dynamic characteristic. The impacting of the valve needle at the end stop positions causes brief but very high contact forces that are transmitted via a housing of the fuel injection valve to the cylinder head and to a fuel distributor rail, in the form of structure-borne sound and vibrations. Among other things, this causes a strong development of noise at the fuel distributor rail.